This technique, for highly active group discussion, can work very well in almost any size group, so long as you have a room with enough tables and chairs so that you can divide the larger group into table groups of, ideally, 4-5 people per table.
Whatever your topic, come up with as many unique questions or discussion sub-topics as you have table groups. Print the question or sub-topic at the top of a piece of flipchart paper that you place on each table, along with coloured markers
Explain the process to the group this way:
World Café is a group facilitation technique that allows all voices to be heard, and for smaller group discussion with a variety of people, at different tables with different topics, leading to large group analysis, questions, discussions and more. It is highly active, it goes quickly, and you get to explore different sub-topics or questions in detail, and also see what others came up about them.
You have 8-10 minutes at this table. First introduce yourselves very briefly, and then begin talking about what is on your flipchart. It is important to print down (legibly, as others will be reading it) all that you talk about. You can appoint a scribe, or everyone can write.
[You can modify the time at each table, or the number of ‘switches’ as you have time and as you wish to organize the discussion. Once people have started, walk around the tables to ensure they are noting what they talk about (you may have to remind them), that they are on topic, to answer any questions, and to tell them when they have 2 minutes left.]
When it is time to switch, ask one person to stay at each table (you can say the person with the biggest wristwatch, someone wearing the brightest colours, the person closest to the door, or however you wish. It is usually quicker and easier to have them assign this way rather than them deciding). Everyone else, disperse to different table (you do not stay as a group).
Do brief introductions, then, the person who stayed: give a brief overview of the discussion at your table, using the flipchart material to guide your 1-2 minute overview. Now, the whole group takes 5-6 minutes (or you can keep it the same as the first timing if you prefer) to discuss both new and existing ideas. You might note where you seek clarification of something already noted, or you might build on it, or add something entirely new.
Continue in this fashion as many times as you wish, with someone else staying at table while the others move to table with a flipchart topic or question they have not yet addressed. Doing a total of 3-5 switches, depending on your overall time, is ideal.
Now, bring the whole group together and ask one person at each table to give highlights of the discussions to date, based on what is on the flipcharts. If there was a need for clarification, maybe whoever noted it in the first place would speak, or someone else would. You want to do this in a punchy sort of way, giving time limits, asking for different things at each table – such as, one highlight, one thing that surprised you, one thing that you disagree with, or that you have had experience with, or??? It all depends on your topic, why you want people to discuss it, what the learning objectives for the session were to begin with, where you want to go with it. It is often a good idea to offer to type up all the material contributed and post it to a website, or send it upon request to anyone who emails you for it.